package com.example.androidproject.activity.utils;
import android.os.Build;

import androidx.annotation.RequiresApi;

import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

 class Sha256Util {



    /**
     * 利用java原生的类实现SHA256加密
     * @param str 加密后的报文
     * @return
     */


    public static String encryption(String str){
        MessageDigest messageDigest;
        String encodestr = "";
        try {
            messageDigest = MessageDigest.getInstance("SHA-256");
            messageDigest.update(str.getBytes(Charset.forName("UTF-8")));
            encodestr = byte2Hex(messageDigest.digest());
        } catch (NoSuchAlgorithmException e) {

        }
        return encodestr;
    }
    /**
     * 将byte转为16进制
     * @param bytes
     * @return
     */
    private static String byte2Hex(byte[] bytes){
        StringBuilder stringBuffer = new StringBuilder();
        String temp = null;
        for (int i = 0; i < bytes.length; i++){
            temp = Integer.toHexString(bytes[i] & 0xFF);
            if (temp.length() == 1){
                //1得到一位的进行补0操作
                stringBuffer.append("0");
            }
            stringBuffer.append(temp);
        }
        return stringBuffer.toString();
    }

}
